elementVector1.add(new DERTaggedObject(0, new ASN1Integer(1)));
        elementVector1.add(new DERTaggedObject(1, new DEROctetString(new byte[] { 0x01 })));
        authVector.add(new DERSequence(elementVector1));

        ASN1EncodableVector elementVector2 = new ASN1EncodableVector();
        elementVector2.add(new DERTaggedObject(0, new ASN1Integer(2)));

        ASN1EncodableVector v = new ASN1EncodableVector();
        // pvno [0] INTEGER 5
        v.add(new DERTaggedObject(true, 0, new ASN1Integer(Integer.parseInt(KerberosConstants.KERBEROS_VERSION))));
        // msg-type [1] INTEGER 14 (AP-REQ)
        v.add(new DERTaggedObject(true, 1, new ASN1Integer(Integer.parseInt(KerberosConstants.KERBEROS_AP_REQ))));
        // ap-options [2] BIT STRING

    @Test
    void testAs_Enumeration_Success() throws PACDecodingException {
        // Test successful casting from enumeration
        Vector<ASN1Integer> vector = new Vector<>();
        ASN1Integer expected = new ASN1Integer(123);
        vector.add(expected);
        ASN1Integer result = ASN1Util.as(ASN1Integer.class, vector.elements());
        assertSame(expected, result);
    }

    @Test
    void testAs_Enumeration_Failure() {

            case 0:
                ASN1Integer pvno = ASN1Util.as(ASN1Integer.class, tagged);
                if (!pvno.getValue().equals(new BigInteger(KerberosConstants.KERBEROS_VERSION))) {
                    throw new PACDecodingException("Invalid kerberos version");
                }
                break;
            case 1:
                ASN1Integer msgType = ASN1Util.as(ASN1Integer.class, tagged);

            ASN1TaggedObject tagged = ASN1Util.as(ASN1TaggedObject.class, fields);
            switch (tagged.getTagNo()) {
            case 0:// Kerberos version
                ASN1Integer tktvno = ASN1Util.as(ASN1Integer.class, tagged);
                if (!tktvno.getValue().equals(new BigInteger(KerberosConstants.KERBEROS_VERSION))) {
                    throw new PACDecodingException("Invalid kerberos version " + tktvno);

        // Create AP-REQ structure
        ASN1Sequence apReqSequence = new DERSequence(new ASN1Encodable[] { new DERTaggedObject(true, 0, new ASN1Integer(5)), // pvno
                new DERTaggedObject(true, 1, new ASN1Integer(14)), // msg-type
        });

        // Create CONTEXT tagged object instead of APPLICATION
        DERTaggedObject contextTag = new DERTaggedObject(false, 14, apReqSequence);

        Enumeration<?> authElements = authSequence.getObjects();
        while (authElements.hasMoreElements()) {
            ASN1Sequence authElement = ASN1Util.as(ASN1Sequence.class, authElements);
            ASN1Integer authType = ASN1Util.as(ASN1Integer.class, ASN1Util.as(ASN1TaggedObject.class, authElement, 0));
            DEROctetString authData = ASN1Util.as(DEROctetString.class, ASN1Util.as(ASN1TaggedObject.class, authElement, 1));

        principalVector.add(new DERTaggedObject(true, 0, new ASN1Integer(1))); // name-type
        principalVector.add(new DERTaggedObject(true, 1, new DERSequence(principalNameVector)));
        v.add(new DERTaggedObject(true, 2, new DERSequence(principalVector)));

        ASN1EncodableVector encPart = new ASN1EncodableVector();
        encPart.add(new DERTaggedObject(true, 0, new ASN1Integer(encType)));

import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.security.auth.kerberos.KerberosKey;

import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.BERTags;
import org.bouncycastle.asn1.DERGeneralString;
import org.bouncycastle.asn1.DEROctetString;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.DERTaggedObject;

                while (adresses.hasMoreElements()) {
                    ASN1Sequence addressSequence = ASN1Util.as(ASN1Sequence.class, adresses);
                    ASN1Integer addressType = ASN1Util.as(ASN1Integer.class, addressSequence, 0);
                    DEROctetString addressOctets = ASN1Util.as(DEROctetString.class, addressSequence, 1);

                    this.userAddresses = new ArrayList<>();